Biomaterial delivery device

ABSTRACT

A biomaterial delivery device includes an elongated handheld powder storage conduit with proximal and distal ends and a bore having a central axis. The proximal end is closed by a movable powder dispensing actuator, and the distal end is closed by an openable sealing nib moveable from its closed to its open position by force upon the actuator. The distal end has a distally-projecting powder discharge chute that spaces the nib away from a surgical site. When the device is held upright over a surgical site with the nib opened, powder passing the nib is deflected at a first oblique direction with respect to the central axis and into or onto the powder discharge chute, and powder striking the chute is deflected at a rotationally distinct second oblique direction orientation with respect to the central axis and into or onto the surgical site.

FIELD OF THE INVENTION

This invention relates to devices for delivering hygroscopic powderedbiomaterials to surgical sites located in or near the respiratory tract.

BACKGROUND

Adenoids (pharyngeal tonsils) and tonsils (palatine tonsils) areinvolved in a number of diseases of the ear, nose, and throat includingchronic otitis media with effusion (COME), recurrent acute otitis media(RAOM), adenoiditis, pediatric chronic sinusitis, tonsillitis, pediatricobstructive sleep apnea (OSA), adult OSA, and chronic strep throat.Lingual tonsils can become infected and may cause or aggravate sorethroat pain. Initial treatment for these various conditions normallyinvolves administration of oral medications or, in the case of pediatricand adult sleep apnea, use of a continuous positive airway pressure(CPAP) device. Otitis media may be treated using ventilation tubesurgery. Treatment success rates are often less than optimal, and inmany cases the tonsils, adenoids or other throat tissue eventually maybe surgically removed. Such surgeries are however painful, typicallyrequire the administration of anesthetics and lengthy post-operativerecovery periods, and may be accompanied by complications such aspost-operative bleeding, dehydration, weight loss, peritonsillarabscess, torticilis (neck stiffness), tissue regrowth, repeat surgery toaddress incomplete prior tissue removal, continued COME or RAOM,continued OSA, and occasionally death. Existing post-surgical treatmentsgenerally provide only limited relief, and may include dietarylimitations, rinses, and administration of painkilling medications ororal antibiotics to reduce post-operative pain and infections.

U.S. Patent Application Publication No. US 2012/0108509 A1 (thedisclosure of which is incorporated herein by reference) describes anartificial scab composition for use in tonsillectomy, adenoidectomy anduvulopalatopharyngoplasty (UPPP) procedures. The composition is asubstantially dry, free-flowing powdered mixture of at least partiallysolvatable chitosan particles and at least partially solvatable oxidizedpolysaccharide particles. When applied to a surgical site or woundmoistened with bodily fluids, the powdered mixture forms aninhomogeneous, uncohesive, solid sheet-like body that breaks apart intosmaller pieces if peeled away from the surgical site or wound. Thepowdered mixture may for example be applied using a bellows-typedispenser that expels the powder through an elongated, flexible strawthat directs a stream of the powder onto a surgical site.

SUMMARY OF THE INVENTION

If not aimed carefully or if excessive force is applied to the bellows,the above-described dispenser can inadvertently direct some or all ofthe powdered mixture into a human patient airway rather than on to theintended surgical site. Doing so is undesirable for a variety of reasonsincluding potential patient safety risk and added delay in completing asurgical procedure.

Once the powder has been dispensed, it usually is desirable to spreadthe powder over the surgical site, e.g., over the floor, walls andpillars of each tonsillar fascia, so as to form a thin film of theapplied biomaterial. Doing so typically may require removal of thedispensing device from the patient's mouth and insertion of a spreadinginstrument, as there may not be sufficient room or viewing space toleave both the dispenser and spreading instrument in place while usingone or the other. If upon spreading it appears that insufficient powderwas applied, it may be necessary to remove the spreading instrument,reinsert the dispenser to apply more powder, and then to remove thedispenser and reinsert the spreading instrument to complete theprocedure. Moreover, because it may be desirable to carry out spreadingpromptly after dispensing, a surgeon may prefer to complete alldispensing and spreading of powder on a first tonsillar fascia beforedispensing and spreading powder on the remaining fascia. This too maynecessitate repeated removal and insertion of the dispenser andspreading instrument.

It may also be desirable to retract nearby tissue while applying orspreading the powder. This may require insertion of an additionalinstrument into an already crowded operating field.

From the foregoing, it will be appreciated that what is needed in theart is a powdered biomaterial delivery device that can dispense andspread biomaterial powders in tonsillectomy, adenoidectomy, UPPP andother surgical procedures near patient airways. Such devices and methodsfor their use are disclosed and claimed herein.

The invention provides in one aspect a biomaterial delivery devicecomprising an elongated handheld powder storage conduit sized for use inthe mouth of a human patient and containing finely-divided powderedsterile biomaterial, the conduit having a proximal end, a distal end,and a bore having a central axis, the proximal end being closed by amovable powder dispensing actuator, the distal end (a) being closed byan openable sealing nib that can be moved from its closed to its openposition by force upon the actuator and (b) having a distally-projectingpowder discharge chute that spaces the nib away from a surgical site,wherein when the device is held over a surgical site with the proximalend uppermost and the nib actuated to its open position, powder passingthe nib is deflected by the device at a first oblique direction withrespect to the central axis and into or onto the powder discharge chute,and powder striking the chute is deflected by the device at arotationally distinct second oblique direction with respect to thecentral axis and into or onto the surgical site.

The invention provides in another aspect a method for applying apowdered biomaterial to a surgical site near a supine human patientairway, the method comprising the steps of:

-   -   a) holding in a generally upright position an elongated handheld        powder storage conduit containing finely-divided powdered        sterile biomaterial, the conduit having a proximal end, a distal        end, and a bore having a central axis, the proximal end being        closed by a movable powder dispensing actuator, the distal        end (i) being closed by an openable sealing nib that can be        moved from its closed to its open position by force upon the        actuator and (ii) having a distally-projecting powder discharge        chute that spaces the nib away from a surgical site, wherein        when the device is held over a surgical site with the proximal        end uppermost and the nib actuated to its open position, powder        passing the nib is deflected by the device at a first oblique        direction with respect to the central axis and into or onto the        powder discharge chute, and powder striking the chute is        deflected by the device at a rotationally distinct second        oblique direction with respect to the central axis and into or        onto the surgical site, and    -   b) applying force to the actuator so that powder is dispensed in        non-atomized form past the nib and towards the surgical site.

The disclosed device and method enable rapid and accurate administrationof powdered biomaterials onto or into surgical site near an airway of asupine patient. The disclosed nib desirably serves as a dump valve andpowder deflector. The disclosed chute desirably serves as a furtherpowder deflector that directs the falling powder onto a desired smalltarget area. The chute desirably is formed in an inclined face of anangled tip having additional surfaces or contours that are usable fordistributing or spreading the powder in or on a surgical site, and forretracting nearby tissue as need be. The disclosed device and methoddesirably permit single instrument gravitationally-assisted powderdispensing, distribution and spreading without requiring the applicationof pressure on a cross-section of the powder itself (e.g., from apiston, plunger, compressed gas or other propellant) to force powder outof the device. This facilitates rapid and readily controllable operationby surgical personnel, and helps discourage aerosolization orinadvertent misdirection of biomaterial powder into the patient airwayrather than into or onto the intended surgical site.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is an exploded view of one embodiment of the disclosedbiomaterial dispensing device;

FIG. 2 is a perspective view, partially in phantom, of the assembledFIG. 1 device;

FIG. 3 is a side orthogonal view of the assembled FIG. 1 device,sectioned along line A-A′ in FIG. 4;

FIG. 4 is a distal end view and

FIG. 5 is a side view of the assembled FIG. 1 device;

FIG. 6 is a perspective view of the FIG. 1 nib;

FIG. 7 is a perspective view of the distal end portion of the assembledFIG. 1 device showing the nib in its closed position;

FIG. 8 is a perspective view of the distal end portion of the assembledFIG. 1 device showing the nib in its open position; and

FIG. 9 through FIG. 15 show various views of the disclosed tips.

Like reference symbols in the various figures of the drawing indicatelike elements.

DETAILED DESCRIPTION

The following detailed description describes certain embodiments and isnot to be taken in a limiting sense. The terms shown below have thefollowing meanings:

The term “airway” means a mammalian breathing passage, e.g., as formedby the mouth, nose, throat and trachea.

The term “average inside diameter” when used in reference to a filledpowdered delivery device having (a) a distal powder delivery outlet and(b) a powder-containing conduit having a central axis, a cylindrical orother cross-section and a constant or varying cross-sectional area alongthat axis means the diameter of a right circular cylinder having aheight and volume like the height and volume circumscribed by the powderwhen the central axis of the filled device is aligned vertically withthe outlet closed and directed downward.

The term “biomaterial” when used in reference to a substance means thatthe substance may be introduced into (and if need be left in) the bodyof a patient as part of a surgical procedure without significantdeleterious or untoward effects upon the body.

The term “free-flowing” when used in reference to a powdered materialmeans the powder will spontaneously flow downhill when placed on ahorizontal surface and the surface rotated to an inclination of about45° to 60° from the horizontal.

The term “gravitational assistance” when used in reference to a powderedsubstance dispensed from an outlet means that the substance passesthrough the outlet primarily due to the influence of gravitationalforces, and

The term “hygroscopic” when used in reference to a powdered substancemeans that the substance takes up and retains water while in solid form(for example, by adsorption, absorption, or as chemically-bound water ofhydration).

The term “loosely-filled” when used in reference to a powdered substancein a conduit or other container means that the substance is not packedinto the container and will rearrange itself within the container if thecontainer is slowly inverted without shaking.

The term “non-atomized” when used in reference to a powdered substancedispensed from an outlet means that a gaseous propellant is not used toaccelerate the substance through the outlet or past the outlet (e.g.,via the Bernoulli effect).

FIG. 1 is a perspective exploded view depicting components that may beused in an embodiment 10 of the disclosed biomaterial delivery device.FIG. 2 depicts a perspective view partly in phantom, of the assembledFIG. 1 device. Retainer 12 is located at the proximal end of device 10and provides a sleeve with openings sized to fit over and capture theend 14 of powder dispensing actuator 16. In the embodiment shown in FIG.1 and FIG. 2, actuator 16 is integrally molded with an elongated andcylindrical, rod-like or stem-like member 18 that can be moved distallyalong the central axis of device 10 by depressing actuator 16 toward thedistal end of device 10. Actuator 16 is integrally molded with anelongated and cylindrical, rod-like or stem-like member 18 that can bemoved distally along the device 10 central axis. Spring 24 biasesactuator 16 toward the proximal end of device 10. Nib 20 at the distalend of elongated member 18 serves as a dump valve for a finely-dividedpowdered sterile biomaterial powder (not shown in FIG. 1) that will becontained in and dispensed by device 10. Nib 20 includes apowder-deflecting ramp 22 that alters the trajectory of powder particlesfalling past ramp 22 by directing the particles at a first obliquedirection with respect to the device 10 central axis. In the embodimentshown in FIG. 1 and FIG. 2 (and as may be seen more clearly in FIG. 6),ramp 22 is concave (e.g., scoop-like) with respect to an axisperpendicular to the main powder flow direction so as to encourage thepowder to remain in contact with ramp 22 as the powder is redirected andto discourage the powder from merely rebounding off ramp 22. Thedisclosed ramp may instead have a generally flat face or may have othernon-flat configurations, for example, concave (e.g., trough-like) withrespect to the main powder flow direction so as to direct the fallingparticles into a laterally more concentrated or narrower pattern as orafter they leave ramp 22 or convex (e.g., domed) with respect to themain powder flow direction so as to direct the falling particles into alaterally broadened pattern as or after they leave ramp 22.

Member 18 fits loosely inside the bore of generally cylindrical orbarrel-shaped conduit 26 so that powder may freely flow between member18 and the inner sidewalls of conduit 26. In the embodiment shown inFIG. 1, conduit 26 has a central cylindrical bore having a uniforminside diameter (and accordingly the same value for its average insidediameter) and a central axis, common with the central axis of elongatedmember 18, along which the movable components of device 10 mayreciprocally move towards and away from the distal end of device 10. Inthe embodiment shown in FIG. 1 and FIG. 2, the device central axis andthe conduit or bore central axis are the same, and unless the contextclearly indicates otherwise these terms may be used interchangeably.Actuator 16 desirably is sized to fit snugly but slidably inside acomplementary cylindrical opening in grip 28. Flange 30 on grip 28assists a user of device 10 in holding, moving and actuating device 10in one gloved hand, for example by holding device 10 with grip 28 placedbetween, and the distal surface of flange 30 in contact with, the user'sgloved thumb and second finger or gloved first and second fingers, whilemeanwhile depressing actuator 16 using the free gloved index finger orfree gloved thumb of the same hand. Meanwhile the user desirably mayalso tilt, rotate, press against, withdraw from or otherwise move device10 as need be with respect to the surgical site.

The distal outlet end 32 of device 10 is connected to adistally-projecting and preferably angled tip 34. One face of tip 34houses a distally-projecting powder-receiving and powder-deliveringdischarge chute 36 whose chute sidewalls (as may be better seen in FIG.14) open toward the central axis of device 10. Tip 34 spaces nib 20 awayfrom a surgical site or other moist tissue surface, thereby helping tominimize moisture entry into device outlet 32 and discourage clogging.Chute 36 receives falling powder particles deflected by ramp 22, andguides or otherwise deflects the received powder particles in arotationally distinct second oblique direction (e.g., with a rotationalorientation with respect to the device 10 central axis that is 180°different than the above-mentioned first oblique direction). Thethus-deflected powder particles are guided or otherwise directed bychute 36 into or onto a desired surgical site. In the embodiment shownin FIG. 1, the sidewalls of chute 36 converge as they approach thedistal end of chute 36, thereby helping to focus or concentrate thefalling particles as or after they pass the distal end of chute 36.

In the embodiment shown in FIG. 1, tip 34 also includes gently-roundedand flattened wing portions 38 a and 38 b which project laterally inhammerhead fashion away from the distal end of chute 36. Wing portions38 a and 38 b help in spreading and packing down the appliedbiomaterial, as well as widening and thereby reducing the pressure perunit area applied by the backside of tip 34 when tip 34 is pressedagainst a surgical site. Wing portions 38 a and 38 b and (as may bebetter seen in FIG. 5) the gently-rounded backside of tip 34 areespecially well adapted for manipulating (for example, retracting)tissue and for raking and spreading the dispensed powder across thefloor and up and down the sidewalls of a surgical site, e.g., atonsillar fascia. The oblique angled orientation of tip 34 (viz., theacute angle of tip 34 with respect to the device 10 central axis)further assists a user in retracting tissue, raking dispensed powderbackwards across a tonsillar fascia floor, raking dispensed powder upthe sidewalls of and into pockets or pillars in tonsillar fascia, andlining up the device outlet above the region at which dispensed powderis desired to land. The respective oblique angles of chute 36 and theramp 22 with respect to the device 10 central axis may each or both bechosen to help regulate the dispensed powder flow rate, with moreoblique angles or more abrupt changes in direction generally causingreduced flow rates, and less oblique angles or less abrupt changes indirection generally causing increased flow rates. The gently-roundedcontours and the absence of sharp edges on nib 20 and especially on tip34 also help minimize surgical site trauma while device 10 is being usedto dispense, distribute or spread powder.

Tip 34 may be firmly connected to the device, for example by beingintegrally molded with conduit 26. If desired, tip 34 may instead beremovable by a user and replaceable or interchangeable with other tipshaving different sizes (e.g., pediatric and adult sizes) or differentshapes or anatomically specific features that better adapt the tip tothe intended surgical site, for example by providing specialized workingsurfaces that assist in depositing or spreading the biomaterial incomplex or unusual surgical sites.

In the embodiment shown in FIG. 1 and FIG. 2, elongated member 18 andthe interior of conduit 26 each have a constant diameter. The tendencyof some powders (for example, hygroscopic powders) to form clumps orcause clogging inside device 10 can be ameliorated by providing aplurality of powder-contacting clump-disrupting projections arrayedinside and along the length of the conduit between the actuator and thenib, the projections being movable in the direction of the device 10central axis by force upon the actuator. Further details regarding suchprojections or regarding the presently-disclosed device may be found incopending U.S. patent application Ser. Nos. (13/781,072, 29/447,060 and29/447,079), filed even date herewith and the disclosures of which areincorporated herein by reference.

FIG. 3 depicts is a side orthogonal view of the assembled FIG. 1 device,sectioned along line A-A′ in FIG. 4. The components shown in FIG. 3 arelike those in FIG. 1 and FIG. 2 but with the addition of a sealingO-ring 23.

FIG. 4 depicts a distal end view and FIG. 5 depicts a side view of theassembled FIG. 1 device. Gently rounded dome 40 on the backside of tip34 faces away from chute 36. Dome 40 can serve among other things todistribute and thereby reduce the pressure per unit area applied by theedge of tip 34 when tip 34 is pressed against a surgical site. Dome 40is especially well adapted for manipulating (for example, retracting)tissue and for raking and spreading the dispensed powder across thefloor and up and down the sidewalls of a surgical site, e.g., atonsillar fascia. The small concave seam (see arrow 42) where theproximal perimeter of dome 40 meets the backside of tip 34 provides anespecially desirable improvement in powder raking and tissue retractionperformance.

FIG. 6 depicts a perspective view of nib 20. Ramp 22 directssubstantially all the falling powder away from the device 10 centralaxis. Ramp 22 does so by deflecting the falling powder at a first angledorientation with respect to the central axis and into or onto powderdischarge chute 36 of tip 34 (not shown in FIG. 6). The end portion 25of nib 20 also includes a discharge outlet sealing surface 27 thatdiscourages powder from passing out of (and discourages powder, liquidsand other materials from entering) the conduit when nib 20 is in itsclosed position.

FIG. 7 and FIG. 8 respectively depict perspective distal end portionviews of the assembled FIG. 1 device showing nib 20 in its closed (FIG.7) and open (FIG. 8) positions. FIG. 8 provides an especially usefulillustration of the changes in powder direction that can arise whenpowder is deflected from ramp 22 to chute 36 while nib 20 is in the openposition.

FIG. 9 through FIG. 15 provide several views of tips for use in thedisclosed device. Most of the individual lead lines and numericidentifiers having been omitted for clarity. FIG. 9 depicts across-sectional view of tip 34 through the device 10 central axis. TheAngle TA may be referred to as the Tip Angle and may for example beabout 4 to about 60, about 4 to about 50, about 6 to about 40 or about 8to about 20 degrees with respect to the central axis. Steeper angles maymake it easier to retract tissue, but may also make it more difficult todirect the dispensed powder onto a desired part of a surgical site.

FIG. 10 depicts a side view of tip 34. The length TL may be referred toas the Tip Length and may for example be about 10 to about 30, about 14to about 25 or about 16 to about 20 mm measured from the device outletto the distal end of tip 34. TL values above about 12 mm are desirablein order to keep the nib dry during use, and values of about 12 to about18-20 mm are desirable for use on pediatric and adult tonsillar fascia.

FIG. 11 depicts a sectional view of tip 34, sectioned along line B-B′ inFIG. 10. Sidewalls 44 a and 44 b in trough 36 help guide the fallingpowder direct it toward the intended surgical site.

FIG. 12 depicts the backside of tip 46. Tip 46 is like tip 34 but lacksdome 40. Tip 46 tends to have less effective spreading, raking andtissue retracting performance than a tip having the disclosed backsidedome.

FIG. 13, FIG. 14 and FIG. 15 are three views of a removable andreplaceable tip 48. FIG. 13 shows a view from the distal end toward theproximal end of tip 48. FIG. 14 and FIG. 15 are respectively threequarter perspective views of the trough side (FIG. 14) and backside(FIG. 15) of tip 48.

The disclosed biomaterial delivery device may be made in a variety ofother embodiments. A number of design goals may be borne in mind whendoing so. For example, the device is as mentioned sized for use in themouth of a human patient, and desirably is sized for use above surgicalsites located in the back of the throat of a supine human patient ofadolescent or adult age. In general for such use there will be adesirable balance between the thinness of the device and the rapiditywith which it can be used to dispense a needed quantity of biomaterialpowder. Desirably the device when inserted through an open patient mouthand directed towards the tonsillar fascia is sufficiently thin so as toleave ample viewing room and space to insert and if need be to operateor manipulate other instruments or objects such as suction lines,lights, retractors (e.g., Hurd retractors) or fingers, e.g., for a handother than the hand used to operate the disclosed device. The devicedesirably also is sufficiently long so that the dispenser when soinserted and directed will reach the back of the patient's throat. Thedevice desirably has sufficiently great powder capacity and sufficientlyrapid powder delivery capability to enable the desired powder amount tobe dispensed, distributed and spread as need be in minimal time, e.g.,in less than two minutes, less than one minute or less than 30 secondsper tonsillar fascia for a tonsillectomy procedure. The device desirablyprovides a line of site view enabling a user to see simultaneously thechute, previously dispensed powder and the area on which powder will bedispensed with the next device actuation. The device desirably is shapedto enable handheld, one-hand operation using either hand. The device mayhowever be made in a variety of diameters and lengths, and may forexample have a conduit with an outer diameter of about 4 to about 15 mm,an average inside diameter of about 5 to about 13 mm, and a lengthmeasured from the finger grip to the device outlet of about 10 to about20 cm for use on tonsillar fascia and longer lengths (for example about10 to about 25 cm) for use in nasal and sinus procedures. The disclosedflange desirably has a diameter of about 20 to about 40 mm, and may beequipped with flattened circumferential portions to keep the device fromrolling when placed on a tray, table or other horizontal surface.

Desirably the device can be rotated at least 360° around its centralaxis while in the mouth, e.g., in order to switch from right-handed toleft-handed use, or to facilitate reorientation of the device such aswhen changing from one tonsillar fascia to the other. Accordingly, thedevice desirably does not include airlines or other potentiallyinterfering appendages.

The device desirably can be used by itself to both dispense and spreadmetered amounts of powder and form a continuous powder coating over theentire surgical site. The device desirably is straight along the entirelength of the conduit, as that can provide better visibility during use,and can provide better leverage and control when spreading powder usingthe tip.

The device desirably meters out an incremental powder portion each timethe actuator is operated. The metered amount will be a function ofseveral factors including the actuator stroke length and geometry, thechosen design for the elongated member and projections (if used), thechosen design for any seals employed, the device outlet size and shape,and the chosen nib design, tip design and associated angles. The devicedesirably permits dispensing to occur whether or not the device distalend is in contact with tissue or other surface, and desirably may beoperated from its proximal end to dispense powder while the distal endis inserted in a patient's mouth without touching the back of thethroat. The device also desirably permits dispensing to occur withouthaving to shake the device. The device desirably is non-pressurized(“non-air-assisted”), does not aerosolize the dispensed powder, anddelivers most or all of the dispensed powder to the intended surgicalsite and none or substantially none of the dispensed powder to thesurrounding tissue or the patient airway. The device accordingly wouldnot be regarded as an inhaler. The delivered biomaterial desirably fallsdown the conduit and through the device outlet primarily or exclusivelydue to gravitational forces, and desirably is not forced out of thedevice due to the action of a piston or other component that appliesforce to the entire cross-sectional area of the dispensed powderportion. The device preferably does not dispense powder or at least asignificant quantity of powder if the device outlet is opened while thedevice is horizontal. The device desirably keeps its powder dry untilsuch time as the dispensed biomaterial contacts the surgical site.Desirably at least the portion of the device housing the storedbiomaterial (e.g., the conduit) and optionally also the elongatedmember, projections (if used) and tip are transparent or translucent.The use of transparent or translucent components can assist a surgeon inmetering a desired powder amount during a procedure and at leastinitially in seeing where best to spread the powder.

The disclosed actuator preferably has a reciprocating actuation motionand more preferably a reciprocating motion along the device centralaxis. The motion desirably is in the distal direction, although anupward actuation in the proximal direction could be employed by using asuitable ledge or grip to facilitate lifting the actuator. The actuatormay if desired use a rotating actuation motion but desirably does do soas such actuation may be more difficult to carry out while holding thedevice in a single gloved hand. For actuation using a reciprocatingmotion along the device central axis, actuation desirably requires arelatively short (e.g., about 2 to about 12, about 4 to about 12 orabout 6 to about 10 mm) stroke and a moderate but noticeable (e.g.,about 1 to about 4 Kg) force. Desirably the actuator (or if desired, oneor more other components such as a projection or projections or the nib)are provided with one or more small ribbed or grooved portions thatengage a nearby complementary recess or tang so as to provide a clickstop or other tactile feedback actuation feature. The recited tactilefeedback may for example occur during or at the end of an actuationstroke. The tactile feedback may also provide accompanying vibrationsthat can help agitate the powder. The disclosed actuator, elongatedmember, projections (if used) and nib desirably are connected to oneanother so that actuation causes all to move (e.g., reciprocate)together. The actuator desirably is provided as part of a componentintegrally molded with at least the nib.

The disclosed nib desirably serves as both a closure valve for thedevice outlet and as a deflector that directs falling powder away fromthe device central axis and into a complementary chute structure in thedisclosed tip. The nib may for example be connected to the actuator viathe disclosed elongated member or may be opened and closed using someother connecting structure. Preferably the nib, elongated member andprojections (if used) are formed (e.g., molded) as a single integralcomponent. The nib preferably discourages the powdered biomaterial fromfalling into areas where it is not intended to be placed and preferablyalso provides tactile feedback of dispenser actuation.

The disclosed conduit preferably has a bore (and most preferably acircular bore) whose diameter does not diminish along the length of thedevice from its proximal to distal ends. Reductions in bore diameternear the proximal end may not be a matter of concern, but reductions inbore diameter near the distal end and especially near the device outletdesirably are avoided. The device outlet preferably has the samecross-sectional shape as the bore (e.g., is circular for a circularbore), preferably is as large as possible, and preferably has a diameterat least 75%, at least 80%, at least 90% or at least as large as theconduit average inside diameter.

The disclosed chute desirably directs the majority and preferably all ofthe falling powder onto a desired small target area that is displacedlaterally from the device central axis. The chute diameter, measured asa chord between the tops of the chute sidewalls, desirably is about 5 toabout 13 mm proximate the nib and about 3 to about 9 mm proximate thedistal end of the chute. The tip desirably has a maximum width at itsdistal end that is at least about 120%, at least about 150%, at leastabout 200% or at least 300% as wide as the chute diameter at the chutedistal end. The above-mentioned Tip Angle desirably is less than 90°with respect to the device central axis. The direction at whichdispensed powder exits the device desirably does not change withsuccessive operations (e.g., strokes) of the device actuator. The tipdesirably lacks sharp edges that might cause tissue trauma, anddesirably includes wings or other powder spreading appendages withrounded distal edges. The tip desirably is sufficiently stiff to permitspreading and tamping the dispensed powder without noticeable tipdeflection. The tip may however be bendable or otherwise formable toaccommodate particular anatomical features or surgical sites.

The disclosed device and its non-powdered components may be made from avariety of materials including acrylics, olefins such as polyethyleneand polypropylene, polycarbonates and other suitable thermoplastic orthermoset materials. The chosen materials desirably have a low tendencyto adhere to the chosen biomaterial powder whether due to static orother attractive forces. The device may also include antistatic surfacetreatments, antistatic additives or surface finishes chosen so as tofurther discourage powder adhesion.

A wide variety of powdered biomaterials may be packaged in the discloseddevice. The biomaterials preferably are organic but for some surgicalend uses may be inorganic materials (e.g., calcium carbonates, zeolitesand other minerals or salts). Exemplary biomaterials may for example benatural materials (e.g., polysaccharides), chemically modified naturalmaterials (e.g, polysaccharide reaction products including oxidized,acetylated, deacetylated, acid-reacted, anhydride-reacted, esterified,neutralized, base-reacted, vinyl-group reacted, isocyanate-reacted orotherwise functionalized polysaccharides, polysaccharide salts and otherpolysaccharide derivatives), or synthetic materials (e.g.,polyglycolides, polyactides, poly(lactide-co-glycolides),poly(ε-caprolactones), poly(dioxanones), polyanhydrides,polyorthoesters, polyethylene glycols and polyvinyl alcohols). Thepowder may be a single material or mixture of materials (for example, amixture of a crosslinkable material and a crosslinker). Exemplarybiomaterials include agars, alginates, carrageenans, celluloses,chitins, chitosan, chondroitin sulfates, dextrans, galactomannans,glycogens, hyaluronic acids, starches, oxidized cellulose, oxidizedchitin, oxidized chitosan, oxidized chondroitin sulfate, oxidizeddextran, oxidized glycogen, oxidized hyaluronic acid, oxidized starchand other materials that will be known to persons having ordinary skillin the art. Suitable biomaterials may be obtained from a variety ofcommercial sources including CarboMer Inc., Monomer-Polymer and DajacLabs, Inc. and Sigma-Aldrich Co. The powdered biomaterial desirably isobtained in dry particulate form, for example, as free-flowing granuleswhose average particle diameter is less than about 1 mm, less than about100 μm, about 1 to about 80 μm, or less than 1 μm. The powderedbiomaterial may be comminuted, lyophilized, crystallized orrecrystallized if desired. If a mixture of particles is employed, theparticles desirably are intimately mixed together prior to placement inthe device, and further mixing desirably is not required at the point ofuse. The biomaterial may provide a variety of features such as theformation of a protective, mucoadhesive, biodegradable, bioresorbable,drug eluting or hemostatic structure (e.g., a layer) followingapplication to a surgical site. The biomaterial preferably issubstantially collagen-free and more preferably contains no collagen atall so as to be saleable worldwide for use without restriction inhumans. The biomaterial may optionally include a variety of otheringredients that are themselves dry, or which when mixed with thebiomaterial will provide or can be processed (e.g., dried) to provide adry powdered biomaterial. Exemplary such other ingredients includeacids, antifoam agents, antimicrobial agents, antioxidants, antistaticagents, bases, buffering agents, colorants, flow aids, hyperosmolaragents, indicators, flavoring agents, sweetening agents, therapeuticagents, modifiers to alter the release rate of therapeutic agents, andother adjuvants that will be familiar to persons having ordinary skillin the art. For example, a useful list of therapeutic agents may befound in U.S. Patent Application Publication No. US 2007/0264310 A1. Thebiomaterials desirably do not contain ingredients which mightpotentially harm mucosal tissues or structures. The disclosed device isespecially desirable for dispensing hygroscopic powders that are proneto clumping or sticking. The disclosed device desirably contains thetotal volume of material to be used in an intended surgical procedure,for example about 0.5 to 2 grams per device for tonsillectomyprocedures.

The disclosed devices desirably are ready-to use items designed forone-time use. Following filling with the desired biomaterial powder, thedevice typically will be placed in suitable sealed packaging (forexample, a metalized foil pouch and optional box) and subjected tosterilization prior to shipment to an end user. Exemplary sterilizationtechniques will be familiar to persons having ordinary skill in the art,and include gamma radiation, electron beam (E-Beam) processing, and coldionizing radiation sterilization (e.g., cold E-Beam sterilization) asdescribed in published PCT Application No. WO 2009/132229 A2.

The disclosed device typically will be used by a surgeon near theconclusion of a surgical procedure. For example, a tonsillectomy oradenoidectomy may be carried out using traditional steps, with tissueexcavation being performed using electrocauterization, snares, scalpelsor other techniques, followed promptly thereafter by use of the deviceto dispense and desirably also to distribute or spread a coating of thedisclosed powdered biomaterial on the exposed fascia. The applicationtechnique is not unlike frosting a cake using the backside of a spoon,but may be carried out much more quickly. Some surgeons may prefer toapply several metered powder doses and then spread the powder, andothers may prefer repeatedly to apply a powder dose, spread the powderand repeat until a desired degree of coating is obtained. As a generalguide, a desirable application rate may be about 10-25 actuations pertonsil dispensing about 0.02 to 0.05 g per actuation stroke.

Although specific and in some cases preferred embodiments have beenillustrated and described, it will be appreciated by those of ordinaryskill in the art that a wide variety of alternate or equivalentembodiments calculated to achieve the same purposes may be substitutedfor the specific embodiments shown and described without departing fromthe present invention. This application is intended to cover anyadaptations or variations of the preferred embodiments discussed herein.Therefore, it is manifestly intended that this invention be limited onlyby the claims and the equivalents thereof.

We claim:
 1. A biomaterial delivery device comprising an elongatedhandheld powder storage conduit sized for use in the mouth of a humanpatient and containing finely-divided powdered sterile biomaterial, theconduit having a proximal end, a distal end, and a bore having a centralaxis, the proximal end being closed by a movable powder dispensingactuator, the distal end (a) being closed by an openable sealing nibthat can be moved from its closed to its open position by force upon theactuator and (b) having a distally-projecting powder discharge chutethat spaces the nib away from a surgical site, wherein when the deviceis held over a surgical site with the proximal end uppermost and the nibactuated to its open position, powder passing the nib is deflected bythe device at a first oblique direction with respect to the central axisand into or onto the powder discharge chute, and powder striking thechute is deflected by the device at a rotationally distinct secondoblique direction with respect to the central axis and into or onto thesurgical site.
 2. The device according to claim 1 wherein the powder isfree-flowing and hygroscopic.
 3. The device according to claim 1 whereinthe powder comprises a polysaccharide, polysaccharide reaction productor polysaccharide derivative.
 4. The device according to claim 1 whereinthe actuator has a reciprocating actuation motion along the centralaxis.
 5. The device according to claim 1 wherein the actuator dispensesabout 0.02 to 0.05 g powder per actuation.
 6. The device according toclaim 1 wherein the actuator has one or more ribbed or grooved portionsthat engage a complementary recess or tang so as to provide a click stopor other tactile feedback actuation feature.
 7. The device according toclaim 1 wherein the nib comprises a powder-deflecting ramp that directssubstantially all passing powder away from the central axis.
 8. Thedevice according to claim 7 wherein the nib ramp is concave with respectto an axis perpendicular to the main powder flow direction so as toencourage passing powder to remain in contact with the ramp as thepowder is deflected and discourage passing powder from rebounding offthe ramp.
 9. The device according to claim 1 wherein the nib comprises adischarge outlet sealing surface that discourages liquids from enteringthe conduit when the nib is in its closed position.
 10. The deviceaccording to claim 1 wherein the actuator and nib are integrally molded.11. The device according to claim 1 wherein the chute directs themajority of passing powder onto a target area displaced laterally fromthe central axis.
 12. The device according to claim 1 wherein the chutehas a distal end, and sidewalls that converge as they approach the chutedistal end, thereby helping to concentrate the passing powder.
 13. Thedevice according to claim 12 wherein the chute has a diameter, measuredas a chord between the tops of the chute sidewalls, of about 5 to about13 mm proximate the nib and about 3 to about 9 mm proximate the chutedistal end.
 14. The device according to claim 1 further comprising a tiphaving gently-rounded and flattened wing portions which projectlaterally away from the distal end of the chute and assist in powderspreading.
 15. The device according to claim 14 wherein the tip has adistal end with a maximum width at least about 120% of the chutediameter proximate the chute distal end.
 16. The device according toclaim 14 wherein the tip lacks sharp edges that might cause tissuetrauma.
 17. The device according to claim 14 wherein the tip has abackside domed portion that assists in retracting tissue and in rakingand spreading dispensed powder across the floor and up and down thesidewalls of a surgical site.
 18. The device according to claim 14wherein the tip is sufficiently stiff to permit spreading and tampingthe dispensed powder without noticeable tip deflection.
 19. The deviceaccording to claim 14 wherein the tip is firmly connected to the device.20. The device according to claim 14 wherein the tip is removable by auser from the device and replaceable or interchangeable with tips havingdifferent sizes, different shapes or anatomically specific features thatbetter adapt the tip to a surgical site.
 21. The device according toclaim 14 wherein the tip extends at an angle of 4 to 60 degrees withrespect to the central axis and has a length of 10 to 30 mm.
 22. Thedevice according to claim 1 wherein the device permits single instrumentgravitationally-assisted powder dispensing, distribution and spreadingwithout requiring the application of pressure on a cross-section of thepowder itself to force powder out of the device, and may be operatedfrom its proximal end to dispense powder while the distal end isinserted in a patient's mouth but does not touch the back of thepatient's throat.
 23. The device according to claim 1 wherein the deviceis non-air-assisted, does not aerosolize the dispensed powder, and canbe rotated at least 360 ° around its central axis while in a patient'smouth.
 24. The device according to claim 1 wherein the device can beoperated with one gloved hand and provides a line of site view enablinga user to see simultaneously the chute, previously dispensed powder andthe area on which powder will be dispensed with the next deviceactuation, and can be used by itself to retract tissue.
 25. The deviceaccording to claim 1 wherein the device keeps its powder dry until suchtime as dispensed powder contacts a surgical site, and delivers most orall of the dispensed powder to the surgical site and none orsubstantially none of the dispensed powder to surrounding tissue or apatient airway.
 26. The device according to claim 1 wherein the deviceis in sealed sterilized packaging.
 27. method for applying a powderedbiomaterial to a surgical site near a supine human patient airway, themethod comprising the steps of: a. holding in a generally uprightposition an elongated handheld powder storage conduit containingfinely-divided powdered sterile biomaterial, the conduit having aproximal end, a distal end, and a bore having a central axis, theproximal end being closed by a movable powder dispensing actuator, thedistal end (i) being closed by an openable sealing nib that can be movedfrom its closed to its open position by force upon the actuator and (ii)having a distally-projecting powder discharge chute that spaces the nibaway from a surgical site, wherein when the device is held over asurgical site with the proximal end uppermost and the nib actuated toits open position, powder passing the nib is deflected by the device ata first oblique direction with respect to the central axis and into oronto the powder discharge chute, and powder striking the chute isdeflected by the device at a rotationally distinct second obliquedirection with respect to the central axis and into or onto the surgicalsite, and b. repeatedly applying force to the actuator so that powder isdispensed in non-atomized form and in a series of incremental portionspast the nib and towards the surgical site.